Macdonald



W. MACDONALD LONG DRAFT CRADLE March 24, 1964 2 Sheets-Sheet 1 Filed April 19, 1962 INVENTOR.

March 24, 1964 w. MACDONALD 3,125,784

LONG DRAFT CRADLE Filed April 19, 1962 2 Sheets-Sheet 2 \E Q h Q INVEN TOR. g6 l/alter'flacab/rau,

25 404 i lh whg United States Patent 3,125,784 LONG DRAFT CRADLE Waiter Macdonald, Seelronk, Mass, assignor to Macdonald and Sons, Inc., Seelronk, Mass, 21 corporation of ode Island Filed Apr. 19, 1962, Ser. No. 188,807 3 Claims. (61. 19255) This invention relates to improvements in long draft cradles of the character used to support the yarn in long draft spinning mechanism.

Cradles of this character are provided with endless aprons or belts used for conducting the yarn fibers from one pair of rolls to the bite of the next succeeding pair of rolls. A cradle supports a pair of belts or aprons and guides these for travel in conducting the yarn fibers between the pairs of rolls.

One form of cradle as used heretofore makes use of parallel bar members often connected together in the form of a hairpin, as tensors for the leading ends of the aprons. One form of cradle is shown in my prior patent application, Serial No. 104,143, filed April 19, 1961, now Patent No. 3,056,174, granted October 2, 1962. However, it is often desired that the outer surfaces of the upper and lower aprons be maintained in continuous contact throughout the length thereof, but this is not practical nor usually provided when the conventional hairpin tensors are employed. In order to obtain the results employed with the hairpin-type tensors and with the continuous contact of the upper and lower aprons, respectively, it has been necessary heretofore to use separate and distinct cradles, replacing one with the other as desired.

One object of this invention is to improve the construction of the cradle to provide therein for the use of tensors that will maintain contact between opposing surfaces of the aprons or to permit the replacement of these tensors by the conventional hairpin-type tensors, if desired, all by the use of a single cradle for either type.

Another object of the invention is to improve the construction of the tensors used for guiding the aprons to effect a proper guiding relation to the aprons and to maintain positive contact between opposing surfaces thereof substantially throughout their lengths.

Still another object of the invention is to provide for the ready removal and replacement of the tensors in the cradle without the necessity for separating parts of the cradle or removing it from the spinning mechanism as, for example, when it is necessary or desirable to alter or change the spacing between the top and bottom tensors or to replace the top aprons.

These objects may be accomplished, according to one embodiment of the invention, by providing a unitary cradle structure which has mountings at one end thereof for removable tensors either of the hairpin-type or of the type made according to this invention. These tensors are so constructed as to be readily replaceable and yet they provide the proper guiding relation for the aprons. One of the tensors should be constructed with a guiding surface for the aprons that would provide the desired curvature thereto. The tensors are so constructed that they may be inserted and removed readily by hand when re placement is desired.

This embodiment of the invention is illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevation of 'a portion of a spinning frame, showing the cradle applied to the roll shafts thereof;

FIG. 2 is a longitudinal section through the cradle;

FIG. 3 is a view of the cradle structure at right angles to FIG. 1;

FIG. 4 is a side elevation of the top tensor constructed according to this invention;

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FIG. 5 is a top plan view thereof;

FIG. 6 is an end elevation thereof;

FIG. 7 is a cross section therethrough on the line 77 in FIG. 5;

FIG. 8 is a top plan view of the bottom tensor;

FIG. 9 is an edge view thereof;

FIG. 10 is an end elevation thereof;

FIG. 11 is a cross section therethrough on the line 111'1 in FIG. 9; and

FIG. 12 is a similar view of the bottom tensor when placed in the cradle in reversed position.

In a conventional spinning frame to which this invention may be applied, the yarn Y is drawn through a series of pairs of roll shafts suitably supported on a roll stand (not illustrated). The sets of rolls shown diagrammatically in FIG. 1 comprise top and bottom back rolls 1 and 2, intermediate rolls 3 and 4, and front rolls 5 and 6. The lower rolls 2, 4 and 6 of the respective pairs are usually mounted in bearings supported in the roll stand and these rolls are positively driven in predetermined timed relation. The upper rolls 1, 3 and 5 rest on the lower rolls 2, 4 and 6, and the yarn Y is drawn through the pairs of rolls, as described and illustrated.

The yarn Y is guided between a pair of aprons 7 and 8 extending over the intermediate rolls 3 and 4 and in substantially parallel runs tangent to the adjacent faces at the bite of the intermediate rolls over guide means provided at the discharge ends of the aprons. Such guide means is usually provided in the form of tensors suitably mounted in a cradle structure which supports the tensors and effects the guiding relation of the aprons 7 and 8.

Any suitable or desired form of cradle structure can be used for supporting the new tensors wherein set forth and claimed, or a conventional form of cradle can be included to use these new tensors as desired.

One form of cradle is illustrated in the drawings, which is substantially that set forth and claimed in my prior application, Serial No. 104,143, filed April 19, 1961, now Patent No. 3,056,174, granted October 2, 1952, and which is made substantially entirely of a relatively rigid, nonmetallic material, as described therein.

This cradle comprises a pair of side plates. 9 and 11 disposed in properly spaced relation, as shown in FIG. 3. The spacing of the plates is accomplished by means of aligned projections 11 and 12 extending inwardly from the resepctive plates at different portions thereof, as shown in FIGS. 1 and 2. These projections 11 and 12 may be secured together as by means of pins d3 and 14, respectively, extending through the projections and securing the structure in a relatively rigid relation. This construction is described more in detail in my application referred to above.

Each of the side plates 9 and lil is formed with a recess r15 for the bottom tensor, and formed in an intermediate portion of the side plate adjacent the leading end of the bottom apron 3. This recess 15 is beneath a projecting tongue 16, the upper surface of which forms a seat 17 substantially at right angles to a back wall 18' in the side plate. At the upper end of the back wall 18 is an outwardly extending shoulder 19. These surfaces 17, 1'8 and 19 form a recess above the tongue '16 in each side plate adapted to receive the top tensor.

The top tensor is designated generally at 2t) and is shown more in detail in FIGS. 4 to 7. The body portion of the tensor 20 is of plate-like form and of a length such that the ends 20a and 20b thereof abut against the inner faces of the side Walls 9 and 19 when the tensor is in place therebetween.

This body portion 20 has a convex and continuously curved bottom face 21 extending throughout the width of the plate-like body portion. The curved upper surface provided for the top portion of the tensor, is for 32 the purpose of reducing the machining costs, as well as assuring a positive match between the upper and lower halves of the mold cavities. Otherwise, the shape may be varied, as desired.

At the opposite ends of the body portion of the tensor 2%) are upstanding lugs 22 of a size and shape to fit in the recesses respectively formed by the surfaces i7, '18 and 19 within the edges of the side plates 9 and till, so as to hold the top tensor in place, as will be described hereinafter. The outer faces of the lugs 22 preferably are provided with means to facilitate gripping as, for example, a series of ribs or serrations, generally indicated at 23 and which are shown as extending vertically along the lugs 22 substantially throughout the outer face of each.

The bottom tensor is provided with a body portion indicated at 24 which is of substantially plate-like form with opposite ends 24a and 24b. In this embodiment, the shape of the bottom tensor body portion 24 is of uniform thickness, with a convex edge portion 25 over which the leading edge of the bottom apron is directed. The opposite edge of the body portion 24 extends beyond the edge of lands 26 and 27 so as to provide means by the ends 24a and 24b for locking the bottom tensor between the side plates 9 and lid.

The body portion of the tensor 24, like the body portion of the tensor 26*, should be of a length between the ends 24a and 24b to extend substantially throughout the distance between the inner faces of the side plates 9 and It and provided with means at opposite ends thereof for mounting the tensor in the recesses provided in the outer edges of the plates.

The mounting means for the tensor 24 comprises lands 26 and 27 formed preferably of one integral piece therewith and molded on the body portion 24. The lands 26 and 27 should be of a size and shape to fit snugly in the recesses 15 in the side plates and thereby to hold the bottom apron in place and in proper guided relation to the top apron.

It will be apparent from FIGS. 9 and ll that the lands 26 and 27 are ofiset vertically trom the body portion 24 of the tensor, being eccentrically disposed from a plane through the center of the latter, as shown in dotted lines in FIG. 10. This makes it possible to reverse the position of the bottom tensor, as illustrated in FIG. 12, and thereby to vary the position of the leading end of the bottom apron.

The bottom tensor 2.4 is adapted to be inserted lengthwise through the apron. To facilitate this insertion, the land 26 thereon is provided with a bevelled end portion 2 8 to direct this land into the recess 15 in the side plate, and also to facilitate the passage of the tensor through the apron. The land 27 is also extended to provide a hand-hold portion 29 on the end of the tensor. The opposite faces of the hand-hold portion 29 preferably is roughened as by means of ribs or serrations 359 to facilitate gripping thereof between the thumb and forefinger during the insertion and removal of the tensor.

In assembling a complete cradle in a spinning frame, the cradle structure 94h?) is first applied to the bottom roll 4 with the apron 8 on the roll 4 and extending forwardly in the direction of travel of the yarn Y. The cradle structure is then in position ready for attachment of the bottom apron by inserting the bottom tensor 24.

The flat bottom tensor 24- is first inserted by being passed lengthwise through the recesses 15 and through the loop end of the bottom apron 8. The bevel-led end 28 will facilitate the lengthwise passage of the tensor 24 as the latter is grasped by the operator between the thumb and forefinger by means of the hand-hold portion 29.

The tensor as can be inserted in its normal position where the body portion thereof occupies the lower section of the recess 15 as shown in FIGS. 1 and 2, or this tensor can be reversed by being inserted from the opposite side of the cradle when it would occupy the relation shown in FIG. 12 of the drawings. In that event, the face of the body portion of the tensor 24 over which the apron passes would be at a higher elevation and closer to the undertface of the top tensor. This makes it possible to provide either a wide opening, as shown in FIG. 2, or more re stricted opening, as shown in FIG. 12, between the upper and lower aprons.

The top tensor 20 has a curved bottom surface 21 to impart the desired degree of curvature to the portion of the top apron 7 in opposed relation to the bottom tensor. This top tensor 2% is held in place by the lugs 22 which fit into the recesses 17, 18, 19 and .is retained by the shoulders 1?. The lugs 22 preferably are formed integral with the body of the tensor 20, being molded in one piece therewith substantially in a triangular relation.

In assembling this top apron on the cradle, the top roll 3 is first inserted inside the apron, and then the tensor 20 is inserted in the opposite end portion of the apron. This loose assembly is then installed by simultaneously placing the top roll trunnions in the notches provided in the upper edges of the sides 9 and ll) of the cradle at the same time that the top tensor 20 is pressed downward against the surfaces of the fingers 16, so that the top ends of the lugs 22 will snap underneath the shoulders 19. As these parts slip into place, the curved bottom surface 21 of the top tensor depresses the lower portion of the top apron 7, and this, in turn, causes the upper portion of the bottom apron 8 to be depressed, thus effecting a desired and proper contact between the aprons.

The same cradle can be used, if desired, with the conventional hairpin tensors. This is made possible by the removal of the tensors 20 and 24 and the insertion of the hairpin tensor, with one side in the recess 15 and the other side thereof directly overlying the surfaces 17 of the fingers 16. The sides of the hairpin tensor will then hold the forward ends of the aprons '7 and 8 in proper relation to each other, but somewhat more spread apart than is the relation illustrated in the drawings. In this way, the same cradle can be used, either to accomplish the type of guiding relation to the yarn provided by this construction or with the conventional guiding action of a hairpin tensor, without requiring that the cradle be replaced entirely in making the change.

Substantially the entire construction, including the frame structure 942, as well as the tensors, can be molded of suitable relatively rigid, non-metallic material, such as a suitable plastic. I have found a material called Delrin that is desirable for this purpose and has the properties of a non-metallic plastic material which is substantially rigid and preserves the perfect alignment.

While the invention has been illustrated and described in certain embodiments, it is recognized that variations and changes can be made therein without departing from the invention, as set forth in the claims.

I claim:

1. A textile drafting apparatus comprising a pair of cooperating upper and lower aprons adapted to be applied to drawing rolls, a pair of front upper and lower apron supporting tensors having the aprons extending thereover in guided relation, unitary cradle structure in cluding side plates for supporting the tensors, said side plates having recesses therein, the lower tensor having a body portion and lands at opposite ends thereof detachably mounted in the recesses, said body portion being offset vertically asymmetrically of the lands.

2. A textile drafting apparatus comprising a pair of cooperating upper and lower aprons adapted to be applied to drawing rolls, a pair of front upper and lower apron supporting tensors having the aprons extending thereover in guided relation, unitary cradle structure including side plates for supporting the tensors, said side plates having recesses therein, the lower tensor having a body portion and lands at opposite ends thereof detachably mounted in the recesses, said body portion being offset vertically asymmetrically of the lands, and means on one end portion of the lower tensor for insertion and removal of the tensor relative to the cradle structure.

3. A textile drafting apparatus comprising a pair of cooperating aprons adapted to be applied to drawing rolls, a pair of front apron supporting tensors having the aprons extending thereover in guided relation, cradle means supporting the tensors, and means detachably mounting the tensors in the cradle means for separation and removal therefrom, one of the tensors having a relatively flat surface in opposed relation to the other tensor and the latter having a convex surface opposite thereto and in guiding relation with the inside of one of the aprons.

4. A textile drafting apparatus comprising a pair of cooperating aprons adapted to be applied to drawing rolls, a pair of front apron supporting tensors having the aprons extending thereover in guided relation, cradle means supporting the tensors, and means detachably mounting the tensors in the cradle means for separation and removal therefrom, the top tensor having a wide body portion with a convex undersurface extending uniformly from one edge portion thereof to the opposite edge portion and in guiding relation with the inside surface of the top apron, and the other tensor having a guiding surface opposed to said convex surface.

5. A textile drafing apparatus comprising a pair of cooperating aprons adapted to be applied to drawing rolls, a pair of front apron supporting tensors having the aprons extending thereover in guided relation, cradle means supporting the tensors, and means detachably mounting the tensors in the cradle means for separation and removal therefrom, one of the tensors having a relatively wide body portion provided with a convex surface toward the other tensor and arranged in guiding relation with the inside surface of the apron extending thereover.

6. A textile drafting apparatus comprising a pair of cooperating aprons adapted to be applied to drawing rolls, a pair of front apron supporting tensors having the aprons extending thereover in guided relation, cradle means supporting the tensors, and means detachably mounting the tensors in the cradle means for separation and removal therefrom, one of the tensors having a relatively wide body portion provided with a convex surface toward the other tensor and arranged in guiding relation with the inside surface of the apron extending thereover and the other tensor having a guiding surface opposed to the convex surface and cooperating therewith to provide uniform bearing relation of the aprons toward each other between the drawing rolls and the tensors.

7. A textile drafting apparatus comprising a pair of cooperating upper and lower aprons adapted to be applied to drawing rolls, a pair of front upper and lower apron supporting tensors having the aprons extending thereover in guided relation, unitary cradle structure including side plates for supporting the tensors, and means for mounting the tensors on the side plates, the mounting means for the upper tensor including recesses in the side plates each formed with upper and lower diverging edge portions substantially in retaining and abutting relation with upper and lower edges of the upper tensor.

8. A textile drafting apparatus comprising a pair of cooperating upper and lower aprons adapted to be applied to drawing rolls, a pair of front upper and lower apron supporting tensors having the aprons extending thereover in guided relation, unitary cradle structure including side plates for supporting the tensors, and means for mounting the tensors on the side plates including a projecting tongue on each side plate between the tensors, each side plate having a recess therein above the tongue with a shoulder overlapping the tongue and spaced there from and with a back edge extending from the shoulder to the tongue, the opposed edges of the shoulder and tongue being in diverging relation for rotating the tensor into and out of engagement with the recess.

References Cited in the file of this patent UNITED STATES PATENTS 2,027,211 Thomas et al. Jan. 7, 1936 2,777,168 Noguera Jan. 15, 1957 2,905,977 Snyder Sept. 29, 1959 FOREIGN PATENTS 564,369 Italy June 14, 1957 

1. A TEXTILE DRAFTING APPARATUS COMPRISING A PAIR OF COOPERATING UPPER AND LOWER APRONS ADAPTED TO BE APPLIED TO DRAWING ROLLS, A PAIR OF FRONT UPPER AND LOWER APRON SUPPORTING TENSORS HAVING THE APRONS EXTENDING THEREOVER IN GUIDED RELATION, UNITARY CRADLE STRUCTURE INCLUDING SIDE PLATES FOR SUPPORTING THE TENSORS, SAID SIDE PLATES HAVING RECESSES THEREIN, THE LOWER TENSOR HAVING A BODY PORTION AND LANDS AT OPPOSITE ENDS THEREOF DETACHABLY MOUNTED IN THE RECESSES, SAID BODY PORTION BEING OFFSET VERTICALLY ASYMMETRICALLY OF THE LANDS. 